Read the following passage and mark the letter A, B, C, D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.
The flag, the most common symbol of national identity in the modern world, is also one of the most ancient. The traditional flag of fabric is still used to mark buildings, ships, and diplomatic cars of nations, but its visual design makes it adaptable for other roles as well. Most flags have a compact, rectangular shape and distinct visual symbolism. Their strong colors and geometric patterns are usually instantly recognizable even if miniaturized to less than a square centimeter. Images of flags can thus serve as identifying icons on airliners, television broadcasts, and computer displays.
Despite its simplicity, the national flag as we know it today is in no way a primitive artifact. It is, rather, the product of millennia of development in many corners of the globe. Historians believe it had two major ancestors, of which the earlier served to indicate wind direction. Early human societies used very fragile shelters and boats. Their food sources were similarly vulnerable to disruption. For all these reasons, they feared and depended on the power of the wind, which could bring warmth from one direction and cold from another.
[I] Some nations, particularly those whose colors and emblems date back several hundred years, have different flags for different official uses. [II] For example, the flag of Poland is a simple rectangle with a white upper half and red lower half. [III] They originated as the colors of the Piast family, which during its rule displayed a crest bearing a white eagle on a red field. [IV] Homage is paid to the Piast Dynasty in the Polish ensign, the flag officially used at sea. Unlike the familiar plain flag flown on land, the ensign has a red shield with a white eagle centered on its upper white stripe.
(Adapted from Cracking the TOEFL iBT)
